Earth boring drill



June 23, 1936.

E. A. REED EARTH BORING DRILL Filed May 18 1934 ZSheets-Sheet 1 June 23, 1936. E. A. REED EARTH BORiNG DRILL 5 F'iled May 18, 1934 2 Sheets-Sheet 2 Patented 'June 23, 1936 UNITED STATES PATENT OFFICE 16 Claims.

This invention relates to improvements in earth boring drills and more particularly to improvements inboring drills of the roller cutter yp One object of the invention is to" provide an improved means for. mounting a roller cutter upon a drill bit body so as to provide for relative rotation therewith and to prevent accidental separation of the cutter from the bit body.

,0 Another object of the invention is to provide an anti-friction bearing for the rollerv cutter which is capable of withstanding the severe'serviceto which a bit of this type is subjected.

Another object of the invention is to provide a stronger means for attaching a bearing member which carries the roller cutter to the bit body so as to prevent separation of the cutter and bearing member assembly from the bit body during operation of the bit.

Another object of the invention resides in the provision of anti-friction roller bearing members which are. effective to prevent separation of the roller cutter and the bearing member upon which it is mounted.

.J A further object of the invention is to provide a means for retaining grease, packed between the interior of the cutter shell and exterior of the bearing member, which means is effective to retain grease in the bearing spaces during the operation of the bit in a well.

A still further object of the invention is' to provide a high pressure slush chamber in the drill head or body which has a plurality of high velocity outlets leading therefrom.

Other objects and advantages of the invention will appear in the following specification of the preferred embodiment of the invention which is shown in the attached drawings of which:

partly in section;

Figure 2 is a partial sectional view of the bit head taken on line 22 of Figure 1;

Figure 3 is an elevation of the bit headlook- 45 ing toward the left in Figure 1; 4 t

Figure 4 is a sectional view taken on line 4-4 of Figure-1, and with the cutter and bearing member assembly removed;

Figure 5 is a side elevation of the bearing mem- 50 ber upon which the cutter is mounted;

Figure 6 is another view of the bearing member taken in a direction indicated by the line 66 of Figure 5;

Figure '7 is a perspective of the lug plate which 55 looks the bearing member to the bit head spindle.

Figure 1 is an elevation of the bit head body diametrically opposed roller cutter assemblies 10 mounted upon individual spindles I! such that inner exterior elements of the roller cutter are substantially in vertical abutting relationship. Since the two roller cutter assemblies and their associated-spindles are identical in con- 15 struction, only one assembly and spindle will be described.

The drill bit body III is provided on its lower portion with projections 18 upon which the spindles I2 are formed integrally therewith and on 20 the lower portion thereof. As shown inFigure 2, the spindle I2 is substantially elliptical shaped in horizontal cross section with the ends of the l ellipse flattened to provide a spindle with flat side surfaces IS. The area of the cross section of the spindle is less than the area of the horizontal cross section of the projections [8, as shown in Figures 1 and 2. That is, the projections l8 are recessed inwardly to form the spindle l2 so as to provide a surface which is normal to the axis of the bit head against which the bearing member I l and the lug plate 2| abut, as will be hereinafter described. The lower. end of the spindle is provided with a frusto-conical surface 20, the opposed elements of which are disposed in substantially right angular relation, with the lower element perpendicular to the axis of the bit head and the inner element parallel to said axis.

The bearing member M is provided with .an interior frusto-conical surface 22 which is adapted" to register with and fit the exterior frustoconical surface 20 of the spindle. As shown in Figures 5 and '6, the exterior surface of the bearing member is in general frusto-conical and is provided with bearing races 23 and 24 to receive roller bearings l6 and II, respectively, (Figure 1). The bearing races 23 and 24 are separated by an annular flange 25 having a bearing surface abutting the roller bearings I6 to form a thrust bearing for the roller cutter, as shown in Figure 1. The smaller end of the bearing member M has the form of an annular flange 25a which has a bearing face presented to the roller bear.-

' cutter.

ings- II to form part of the thrust bearing above referred to. The base end of the frusto-conical roller cutter I5 is provided withan internal annular flange 29 to retain the roller IS in position,v

and this flange is further provided withan annular recess 30 which receives an annular flange 3| provided near the base of the bearing member H in bearing engagement to provide a grease seal between the roller cutter and the bearing memher. It is to be noted that the elements of the circumferential face of this flange are parallel to the axis of the' cutter so that the cutter may be assembled upon the bearing member by a motion parallel to the axis of the cutter- The flang'e 29 also has a bearing face abutting the roller bearings l6 which also forms a thrust bearing to retain the roller cutter upon the bearing member l4.

The roller bearings l6 and I! are of tapered formation and the bearing races of the bearing member l4 and cutter l5 have surfaces of frustoconical formation in rolling contact with the tapered surface of the roller bearings. These frusto-conical surfaces of the bearing races 23 and 26 of the bearing member and the roller cutter respectively, have a common apex, b'y projection, substantially coincident with the apex of the-frustmconical external Surface of the roller The similar frusto-conical surfaces of the bearing races 24 and 21 are of different angularity than the surfaces of bearing races 23 and 28 and have a common apex which is coincident with the axis of the roller cutter, but which is spaced from the apex of the external frustoconical surface of the roller cutter in order that the two sets of roller bearings l6 and I1 may more efficiently transmit the different stresses to which they are subjected.

In order that the roller bearings l6 and I! may be placed within the bearing races, the bear-' ing member I4 is provided with bores 32 and 33 through which the roller bearings are inserted into the bearing races. When the device is assembled, those bores 32 and 33 are closed by plugs, one of which is shown at 34 in Figure 1. These plugs 34 are sections of the bearing member and have inner surfaces registered with frusto-conical surface 20 of the spindleand, outer surfaces registering with the bearing surfaces of the bearing races 23 and 24.

In manufacture the bearing member. I4 is brought roughly to form, the bores 32 and 33 are drilled, the sections 34 are then inserted, and the bearing member machined to final form. The sections 34 are then removed and the cutter l5 and bearing me ber 4 placed in assembled relation. The rollers l6 and I1 are'then inserted and the bearing races packed with grease, after which the sections 34 are again inserted and welded into place as indicated at 35. A final machining of the interior surface of the bearing member I4 may then be necessary. This roller bearing cutter and bearing member assembly may be furnished as a complete article of menufacture supplied to. 'drill operators to be installed upon a bit head. It is noted that there is no relative movement between the spindle 2 and the bearing member l4, and that all wear takes place within the replaceable cutter and bearing member assembly.

To secure the bearing member to the spindle a lug plate 2| is provided with lugs 38 which engage with the notches 31 provided in extending portions 38 of the bearing member I4, which portions extend laterally from the spindle |2 beyond the roller cutter when the bearing member and cutter assembly is positioned upon the spindle. The lug plate 2| partially surrounds the spindle i2 and closelyfits the spindle, as shown in Figure 2. The lower edge 31a of the lug plate 2| is formed to closely fit the internal frusto-conical surface 22 of the bearing member l4 and may be assembled with the bearing member by a movement parallel to the axis of the lugs, 36. In practice, the lug plate is assembled with the bearing member before placing the same upon the spindle and is welded to the bearing member along the lower edge 31a of the lug plate, as indicated at 38a, Figure 1. The lug plate 2| may' be assembled with the bearing member and cutter assembly to form a complete article of manufacture which may be furnished to drill operators as above indicated. This assembly, including the lug plate, may be placed upon the bit head by a movement parallel to the axis of the bit head body.

The lug plate 2| is provided with a tapered bore 39 which registers with a screw threaded bore 48 in the spindle I 2 when the lug plate is sitioned in a direction axially of the drill head, 40

with respect to the. base area of the spindle, which area is defined by the intersection of said spindle with the projection I8 of the drill head. That is, the spindle is not undercut at any place and there is no localized stressv adjacent the op- 45 eration of the drill. Also, as shown in Figure 1,

the upper edge of the lug plate 2| and the edge of the bearing member M in contact with the projection .|8 of the drill head form a force transmitting surface abutting the projection I8 of 50 the drill head. This construction provides for transmitting a large portion of the forces to which the roller cutter is subjected directly to the massive body of the drill head independent- 5 ly of the spindle.

As shown particularly in Figure 4, drill head I8 is hollow and is formed with an inverted T- shaped chamber 42 which-.is in communication with the interior of the threaded box II which (not shown) through which a circulating fluid is supplied to the drill head. The chamber 42 communicates with the exterior of the drill headthrough opposed bores 43 closed by screw threadcommunicates with the interior of a drill pipe 60 ed plugs 44 in order to allow cleaning of the in- 65 terior of the drill head in the event that it becomes clogged with solid matter in the circulating fluid. The lower portion of the drill head is provided with a plurality of spaced bores 45 connecting the chamber 42 with the exterior of the drill. Preferably, the bores 45 are screw threaded and pipe nipples 43 inserted therein to prevent wear upon the drill head body Ill, due to abrasives in the circulating fluid which will normally unduly enlarge the bores through amasss which the fluid is injected into the drill hole.

The pipe nipples may be cheaply and quickly replaced when they become worn by the circulat hole during operation as desired for emc'iency in w the bottom of the hole and cutting formations or strata.

' While I have shown and described the pre-' ferred embodiment of my invention, it is to be understood that the present invention is not to be limited tothe precise details of construction herein shown and described. It is therefore my intention that the scope of my invention be unrestricted other than by the appended claims.

I claim as my invention:

1. In a deviceof the character described, the combination with a drill head having a vertically disposed cutter supporting spindle with a frustoconical surface at its lower end, of a bearing member having substantially frusto-conical external and internal surfaces, the latter surface being adapted to engage the frusto-conical surface of said spindle, a. roller cutter having substantially frusto-conical bearing surfaces, said bearing member having a plurality of raceways formed in the external surface thereof and said roller cutter having a plurality of complemental raceways in the internal surface thereof, antlfriction rollers disposed within said complemental raceways for preventing longitudinal movement of said bearing member and said roller cutter relative to each other and providing for relative rotation with respect to each other, means carried by said bearing member and embracing said spindle for locking said bearing member and spindle againstrelative rotation, and means to lock said bearing member and spindle in assembled relation.

2. In a device ofuthe character described, the combination with a drill head having a vertically disposed cutter supporting spindle with a frustoconical surface at its lower end, of a bearing member having substantially frusto-conical external and internal surfaces, the internal surface of said bearing member being adapted to engage the frusto-conical surface of said spindle and the external "surface of saidibearing member being formed with a plurality of annular channels surrounding it, a roller cutter having an internal substantially frusto-conical surface, said cutter having a plurality of annular channels formed in the internal surface thereof adapted to register with the plurality of annular channels formed in the external surface of said bearing ed to close said apertures to register with the' external and internal surfaces of said bearing member, means on saidbearing member adapted to interlock with said spindle whereby rotation of said bearing member with respect to said spindle is prevented, an annular projection formed on the external frl1sto conical' surface of said bearing member, said cutter having an annular depression :formed in the internal frusto-conical surface thereof adapted to receive said annular projection in grease sealing engagement therewith, and interlocking means between the means on said bearing member and spindle to prevent axial separation of said spindle and bearing member, said means including a pin having a head disposed in a bore through said means on said bearing member and engaging said spindle by means of screw thread.

3. In a device of the character described, the

combination with a drill head having a vertically disposed cutter supporting spindle with a frustoconical surface at its lower end, of a bearing member having substantially frusto-conicalexternal and internal surfaces, the latter surface being adapted to engage the frusto-conical surface of said spindle, a roller cutter having a substantially frusto-conical internal surface, said bearing member having a. plurality of raceways formed in its external surface, said roller cutter having a plurality of complemental raceways formed in its internal surface, anti-friction rollers disposed within said complemental raceways for preventing longitudinal movement of said bearing member and said roller cutter relative to each other while providing for relative rotation with respect to each other, the frustoconical walls of the hearing member extended outwardly beyond the interior of the cutter and having notches formed therethrough adjacent the outer marginof said bearing member, a lug member formed to seat on the interior of said bearing member and provided with means interlocked with said notches, said lug member having portions thereof welded to said bearing member, the interior of said lug member beingadapted to snugly fit an exterior surface of said spindle and to be mounted thereon by sliding the same in a. direction parallel to the vertical axis of said spindle, and means to interlock said lug member and said spindle against relative movement.

. 4. In a device of the character described, the

.extemal and internal surfaces, the latter surface being adapted to engage the frusto-conical surface of said spindle, a roller cutter having a substantially frusto-conical internal surface, said bearing member and cutter having a plurality of complemental raceways in the form of tapered annular channels formed in the external surface of said bearing member and in the internal surface of said roller cutter, anti-friction rollers disposed within said complemental raceways, for

preventing longitudinal movement of said bearing member and said roller cutter relative to each other while providing for relative rotation with respect to each other, the frusto-conical walls of the bearing member extended outwardly beyond the interior of the cutter, slots formed through the frusto-conical walls of the bearing member adjacent its outer margin, a lug member formed to seat on a segment of the interior of said bearing member and provided with means adapted to interlock with the aforesaid slots or notches formed through the frusto-conical walls of the bearing member, means to fasten said lug member to said bearing member in interlocked relation, the interior of said lug member being adapted to snugly flt an exterior surface of said spindle and to be mounted thereon by sliding the same in a direction parallel to the vertical axis of said spindle, said spindle being recessed inwardly from the margin of the'drill head so as to leave a flat surface on said drill head, the top of said lug being seated against said flat surface so as to be supported thereby, said bit head having provided thereunder a shoulder, having a face at right angles to the vertical axis ofthe spindle, the top of the inner wall-of the bearing member being flattened to flt said shoulder and seated thereon to be supported thereby, and means coacting with the lug of the bearing member and said spindle to maintain them free from relative axial movement.

5. Asan article of manufacture, a bearing member having an internal frusto-conical surface, said bearing member having apertures through the frusto-conical surface, said apertures being spaced from the apex of said conical surface, and closures for said apertures having surfaces registering with said frusto-conical surface.

6. As an article of manufacture, a bearing member having internal and external frust'oconical surfaces tapering in similar directions, the external frusto-conical surface being formed with raceways in the form of tapered annular channels, the bearing member having apertures formed through the frusto-conical surfaces and opening into said raceways, and closures for 'said apertures having surfaces registering with the internal surface of said bearins member and the bearing surfaces of said raceways 7. In adrill, the combination with a drill head of a bearing member secured thereto having an internal frusto-conical surface and a plurality of external frusto-conical surfaces tapering in the same general direction but of different angularity, an annular flange projecting from the external surface of said bearing member and adapted to serve as a thrust bearing for anti-frictionroller bearings, a roller cutter having a plural: ity of internal frusto-conical surfaces tapering in the same general direction but of different angularity, said roller cutter having an annular channel formed in the internal surface thereof receiving said annular flange, said annular flange being disposed within said channel but incompletely filling the same, anti-friction roller bearings disposed within the remainder of said channel and abuttingsaid flange and a wall of said channel to prevent axial separation of said rollercutter and said bearing member, said hearing member having an aperture therethrough opposite said channel providing means for introducing said anti-friction roller bearings into said channel, and a section of bearing member having surfaces registering with the external surface of said bearing member closing said aperture and fastened to said bearing member.

8. In a drill, the combination, with a drill head of a bearing member secured thereto having a plurality of external frusto-conical surfaces tae pering in the same general direction, but of different angularity,-an annular flange projecting from the external surface of said bearing member and adapted to serve as a thrust bearing for anti-friction roller bearings, a roller cutter having a plurality of internal frusto-conicalsurfaces tapering in the same general direction, but of different angularity, said cutter having an ana member and adapted as anti-friction rollers, anti-friction rollers disposed .nular groove formed in the internal surface thereof receiving said annular flange, said annular flange being disposed within said groove but incompletely fllling the same, anti-friction roller bearings disposed within the remainder of said 5 groove andabutting said flange and a wall of said groove to prevent axial separation of said roller cutter and said bearing member, said bearing member having an aperture through said bearing member opposite said groove providing means to introduce said anti-friction roller bearings into said groove, and a section of bearing member having surfaces registering with the external surface of said bearing member closing said aperture and flxed in position in said bear' ing member. 9. As an article of manufacture, a bearingmember having a plurality of external frustoconical surfaces tapering in the same general direction, but of different angularity, an annular flange projecting from the external surface oi. said bearing member and adapted to serve as a thrust bearing for anti-friction roller bearings, sa'id bearing member having an aperture therethrough spaced from its apex, and a section of 25 bearing member closing said aperture and having an external surface registering with the external surface of said bearing member which extends circumferentially from said aperture.

10. As an article of manufacture, a roller cutter 30 having a plurality of internal frusto-conical surfaces taperin in the same general direction, but of different angularity, said roller cutter having an annular channel formed'in the internal surface thereof adapted to receive anti-friction roller 35 bearings and a thrust bearing member for one end of said roller bearings.

11. In a drill,'the combination with a drill head of a cutter assembly comprising a roller cutter; member having an external substantially frusto- 40 conical surface and a plurality of internal frustoconical surfaces tapering in the same general direction, but ofdifl'erent angularity, one of which said internal frusto-conical surfaces, by projection, having its apex substantially coincidental with the apex oi the external frusto-conical surface of the roller cutter, an annular flange bounding the base end of said frusto-conical surface and adapted as a thrust bearingfor anti-friction rollers, and a bearing member having a plurality of external frusto-conical surfaces tapering in the same general direction, but of different angularity. oneof which said frusto-conical surfaces, by projection, having its apex substantially coincidental with the apex of the external frusto-conical surface of the roller cutter within which it is disposed, said last named frusto-conical surface being opposite and complemental to the like surface in said roller cutter, and spaced apart therefrom, an annular flange boundingfltheapical end of said frusto-conical surface of said bearing a thrust bearing for within the space between said complemental Y frusto-conical surfaces and abutting both of said flanges, one of said members having an aperture therethrough to provide means for inserting antifriction rollers intosaid space, a plug closing said hole-having an end completing the frustoconical surface of the member through which said hole extends, and means for fastening said plug in flxed position.

12. The combination described in claim 11, in which said roller cutter is provided with an annular groove in the internal sin-race thereof, and

.of said spindle being formed with an external said bearing member is provided with an opposite and complemental groove, the bottom of each of said grooves being frusto-conical in form and having the bases thereof extending in the same direction as the bases of the members in which they are formed, and disposed so that their apexes, by projection, are not coincidental with the apex of the external surface of the roller cutter enclosing them, tapered roller bearings disposed within and substantially filling said grooves to prevent axial movement of said rollercutter and said bearing member relative to each other, one of said members having an aperture to provide means for inserting roller bearings into said grooves, a closure for said aperture and means v to fix said closure in position. I

13. .In a cutter assembly, the combination of a bearing member and a roller cutter member, both having substantially internal and external frustoconical surfaces, the internal surface of the cutter member and the external surface of the bearing member, having bearing engagement with each other, a plurality of raceways between said members adapted to receive tapered roller bearings to prevent axial movement of said members relative to each other while providing for free rotation of said members relative to each other, a set of tapered roller bearings disposed within each said racefway, one of said sets of'said tapered bearings so disposed that the apex of each ta-' pered roller thereof by projection is substantially coincidental with the apex of the external surface of the roller cutter, and another set of said tapered roller bearings so disposed that the apex of each tapered roller thereof, by projection, is not substantially coincidental with the apex of the external surface of the roller cutter, and means providing for inserting said tapered roller bearings and holding them in raceways.

14. In a rotary drill, a drill head body having a spindle projecting therefrom, the projecting end frusto-conical surface, a bearing member for rotatively supporting a rotary cutter, said bearing member having an interior frusto-conical surface engaging the frusto-conical surface of said spindle, a locking member for retainingsaid hearing member upon said spindle, said locking member engaging a portion of said interior frustoconical surface and said drill head body for transmitting a portion of the stress to which said bearing member is subjected during drilling directly from said bearing member to said drill head body.

15. In a rotary drill, a rotary cutter member rotatively :Iournaled upon a bearing member, said bearing member being provided with integral annuiar flanges uponlts outer surface defining a bearing race for receiving roller bearings, said rotary cutter nrember being provided with integralannular flanges ,upon its inner surface de- 20 fining a bearingvrace complementary to said first mentioned bearing race for receiving said roller bearings, said roller bearings coacting with said annular flanges to prevent axial separation of said members, one of said members having an 25 aperture through the bearing surface of'its bearing race to provide for insertion of said roller bearings, and a closure for said aperture having a bearing surface registering with said bearing surface. I 16. In a drill having a drill head, the combination of a support depending from said drill head, a removable cutter support surrounding said depending support, a cutter rotatably mounted thereon and having its axis of rotation at an angle to the direction of removal of said outter support, means to prevent relative rotation and separation of said supports, and means to prevent axial separation of said cutter and said cutter support.

EARL A.- REED. 

